Creating weak_ptr<> from raw pointer

c++ pointers boost weak-ptr
Loom picture Loom · Oct 2, 2013 · Viewed 16.9k times · Source

I'd like to wrap raw pointer member to some smart pointer to prevent deleting inside a developing class. Owner of the object under pointer is outside of class. So, looks like boost::shared_ptr and std::auto_ptr does not fit. The following is a reduced example:

class Foo {
  boost::weak_ptr<Bar> m_bar;
public:
  void setBar(const Bar *bar) { // bar created on heap
    m_bar = bar;                // naturally compilation error
  }
};

Of course, it induces compilation error. What is a correct way to initialize weak_ptr from a raw pointer (if exist)?

Answer

Julien Lopez picture Julien Lopez · Oct 2, 2013

You can't do that, you can only create a weak_ptr out of a shared_ptr or another weak_ptr. So the idea would be that the owner of the pointer hold a shared_ptr instead of a raw pointer, and everything should be ok.

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